Biomedical subjects

S Oki

Publications and source records attributed to S Oki.

At least 55 records · Page 3Linked to original sources

PubMed1996

Anomalous left main coronary artery arising from the pulmonary artery in an adult: treatment by direct reimplantation.

We herein report the case of a 37-year-old woman in whom an anomalous origin of the left coronary artery from the pulmonary artery was surgically corrected. A magnetic resonance angiogram showed the left main coronary artery connecting to the right posterior portion of the pulmonary trunk, and exercise-stressed thallium-201 perfusion scintigrams demonstrated a large reversible anterior defect. She was successfully treated by direct aortic reimplantation of the abnormal left coronary artery. We were able to obtain a sufficient length of the left main trunk by excising the large cuff of pulmonary artery wall surrounding the ostium of the anomalous left coronary artery while transecting the pulmonary artery. Postoperative angiograms demonstrated a widely patent left coronary artery, a decrease in the size of the right coronary artery, and no collaterals, and exercise-stressed thallium-201 perfusion scintigrams demonstrated no remaining ischemic defect at all. Direct aortic reimplantation is an ideal operation but is still limited by the anatomical position of the left coronary artery. In this case, magnetic resonance angiography was an excellent method for deciding the optimum operative procedure for the anomalous left coronary artery. In addition, exercise thallium-201 scintigraphy was found to be useful in recognizing the revascularized effect of the left ventricle.

Adult↗

PubMed1996

Male sexual function after autonomic nerve-preserving operation for rectal cancer.

PURPOSE: Sexual dysfunction after surgery of the rectum is a serious complication to male patients. Autonomic nerve-preserving operation for rectal cancer has been performed within the recent ten years to maintain urinary and male sexual functions without spoiling of therapeutic radicality. To clarify male sexual function as the degree of autonomic nerve-preserving operation, the function was outlined through clinical interview. METHOD: In a series of 134 male patients who were undergoing autonomic nerve-preserving operation for rectal cancer, a detailed history of postoperative sexual function was obtained by interviews. RESULTS: In 87.7 and 66.9 percent of patients, erectile and ejaculatory potencies were maintained, respectively, which were higher rates than those after extended and conventional pelvic dissections. According to the preserving extent of autonomic nerve, patients undergoing complete preserving operations showed higher rates of maintained erectile (92.9 percent) and ejaculatory functions (82.5 percent), sexual intercourse (89.9 percent), and orgasm (93.9 percent) compared with those undergoing hemilateral autonomic nerve-preserving (82.3, 47.1, 52.9, 64.7 percent) or partial pelvic plexus-preserving operation (61.1, 0, 26.3, 22.2 percent). CONCLUSION: Pelvic plexus preservation is necessary to maintain erectile potency, and both hypogastric nerve and pelvic plexus preservation are necessary to maintain ejaculate function and orgasm. To maintain satisfactory sexual function, complete autonomic nerve-preserving operation is suitable.

Aged↗

PubMed1996

99mTc-MIBI accumulation in the parathyroid autograft in a patient with recurrent hyperparathyroidism.

A case with recurrent hyperparathyroidism secondary to chronic renal insufficiency is reported. The patient had undergone total parathyroidectomy and autotransplantation of parathyroid tissue five years ago. Bone scintigraphy clearly demonstrated skeletal involvement of secondary hyperparathyroidism and 99mTc-methoxyisobutylisonitrile scintigraphy clearly demonstrated a hyperfunctioning parathyroid autograft.

Bone and Bones↗

PubMed1996

Occlusion of the semicircular canal using argon laser.

The effects of argon laser on the bony semicircular canals were studied in the guinea pig. After intraperitoneal administration of Nembutal, the bulla was opened in order to approach the lateral and posterior canals. The anterior canal was approached through the posterior fossa. The argon laser was applied through a probe which was connected to a device from HGM Medical Laser Systems. One of the three semicircular canals was irradiated one to several times by argon laser (1.0-1.5 W x 0.5 sec). Histopathologic examination of the temporal bones revealed that the semicircular duct shrank immediately after irradiation. The laser produced a charred area in the bony canal wall. The semicircular canals gradually became fibrotic and ossified and completely occluded within several weeks. Heat produced in the bony canal may be responsible for the morphologic changes. On delayed observation, the cochlea of the canal-irradiated animals showed no morphologic changes. Auditory brain stem responses were normal. Caloric stimulation using 5 ml/5 sec of ice water revealed no response in the lateral canal-irradiated animals.

Animals↗

PubMed1996

Endothelial pores in the rat soleus muscle capillaries after experimental limb immobilization.

Structural changes of capillaries were reexamined in the rat soleus muscle 12 weeks after limb immobilization. Most capillaries were of the continuous type, while capillaries with fenestrations were often observed around degenerated muscle fibers. In some of these fenestrated capillaries, the endothelial cell was partially disrupted and formed a small pore at its fenestrated portion. These findings suggest that the occurrence of capillaries with both diaphragmed fenestrae and pores represent degenerative changes in the long-term immobilized muscle.

Animals↗

PubMed1996

Morphological changes of capillaries associated with muscle-fiber atrophy in the extensor digitorum longus muscle of aged rats.

We examined the structural changes of continuous capillaries in the extensor digitorum longus muscle of 6, 12 and 24-month-old normal rats. Capillaries around each muscle fiber in the sixth month were of the continuous type. In the 12th month, muscle fibers appeared almost normal except for widened intercellular spaces and degenerative changes in the subneural sarcoplasm. In the 24th month, many muscle fibers atrophied having greatly reduced diameter and irregular cross sectional profiles. Capillaries in the widened interstices, both in the 12th and 24th months, were embedded in an abundant amount of connective tissue components, including collagen fibrils and amorphous substances, and were surrounded by basal laminae arranged in concentric lamellae. Capillaries in the abundant connective tissues were mostly of the continuous type, while 10% in the 12th month and 20% in the 24th month consisted of endothelial cells with fenestrations bridged by a single-layered diaphragm. In some of the fenestrated capillaries in the 12th month, endothelial cells became partially disrupted and formed pores at the fenestrated portions. These findings confirm that intramuscular capillaries degenerate following the partial atrophy of muscle fibers, and suggest that the occurrence of fenestrations in the endothelial cells represent a first step in the degeneration of continuous capillaries.

Animals↗

PubMed1996

[Flow cytometric DNA analysis of malignant potential in colorectal cancer].

Significance of flow cytometric DNA analysis for assessing malignant potential and survival of colorectal cancer was investigated using paraffin-embedded materials from 163 patients who underwent resection of curability A from 1971 to 1985, excluding intramucosal carcinoma. DNA diploid was confirmed in 46% (75 cases) of the patients and DNA aneuploid in 54% (88 cases). No significant correlation was seen between DNA ploidy and clinicopathological factors, such as tumor location, macroscopic type, histological type, depth of invasion, lymph node metastasis and stage. Cumulative survival rates after curable resection of colorectal cancer were significantly lower in patients with DNA aneuploid tumor than those with DNA diploid tumor. Furthermore, in patients in stage of II and III, survival rates were lower in DNA aneuploid patients than DNA diploid patients, respectively. A multivariate analysis of survival data using Cox's proportional hazard model showed that DNA ploidy was the significant discriminating factor on survival in stage II and III cancer. In conclusion, nuclear DNA ploidy in patients with stage II and III colorectal cancer undergoing curable resection may represent malignant potential and may be an independent prognostic factor.

Colorectal Neoplasms↗

PubMed1995

Atlanto-occipital hypermobility in subjects with Down's syndrome.

STUDY DESIGN: The upper cervical spines of 57 subjects with Down's syndrome were retrospectively examined, with special attention to atlanto-occipital mobility. OBJECTIVE: To examine the magnitude of atlanto-occipital mobility and its clinical significance in subjects with Down's syndrome. SUMMARY OF BACKGROUND DATA: Atlanto-occipital translation of more than 1 mm in adults implies instability. However, the normal value in children with Down's syndrome has not been established, and the value in Down's syndrome has not been evaluated based on a comparison between subjects with Down's syndrome and control subjects. METHODS: Measurements were made by Wiesel and Rothman's method in 38 subjects with Down's syndrome and 34 control subjects. RESULTS: Atlanto-occipital translation in the Down's syndrome group ranged from 0-6.4 mm (mean, 2.3 mm), whereas in the control group it ranged from 0-2.1 mm (mean, 0.61 mm). The difference was statistically significant. Of the 38 subjects with Down's syndrome, 37 were asymptomatic. CONCLUSION: The magnitude of atlanto-occipital translation, as expected, apparently was greater in subjects with Down's syndrome than in control subjects. Although the possibility of neurologic complications should be considered whenever unusually high atlanto-occipital mobility is seen, a majority of the subjects with Down's syndrome were asymptomatic.

Adolescent↗

PubMed1995

Detection of cytomegalovirus DNA in urine from newborns in NICU using a polymerase chain reaction.

To investigate the natural course of viral shedding during the newborn period, the presence of Cytomegalovirus (CMV) DNA in specimens at 3, 7, 14, 21 and 28 days of life was examined using the polymerase chain reaction (PCR) method. At the 3rd day of life, the viral DNA positive rate in the urine was 7% (4/60), at the 7th day 7% (3/46), at the 14th day 10% (2/20), at the 21st day 10% (1/10), and at the 28th day 25% (1/5). CMV was also detected in samples co-cultivated with HeLa 229 cells and this positive rate was 5% (3/60). The viral positive rate in newborns did not correlate with the gestational age, body weight, or serum IgM level. Six congenital infection cases were identified; two of which were small-for-date babies (SFD) and three of which were born with premature rupture of membranes (PROM). They had no complications during the six months after birth.

Cytomegalovirus↗

PubMed1995

Tentorial meningioma and painful tic convulsif. Case report.

A case is presented of painful tic convulsif caused by a posterior fossa meningioma, with right trigeminal neuralgia and ipsilateral hemifacial spasm. Magnetic resonance images showed an ectatic right vertebral artery as a signal-void area in the right cerebellopontine angle. At operation the tentorial meningioma, which did not compress either the fifth or the seventh cranial nerves directly, was totally removed via a suboccipital craniectomy. The patient had complete postoperative relief from the trigeminal neuralgia and her hemifacial spasm improved markedly with decreased frequency. From a pathophysiological standpoint, the painful tic convulsif in this case was probably produced by the tumor compressing and displacing the brainstem directly, with secondary neurovascular compression of the fifth and seventh nerves (the so-called "remote effect").

Aged↗

PubMed1995

[Pharmacokinetic, bacteriological and clinical studies of SY5555 in the pediatric field].

Pharmacokinetic, bacteriological and clinical studies on SY5555, a new oral penem, were carried out, and the following results were obtained. 1. MICs were determined for 6 drugs, SY5555, clavulanic acid/amoxicillin (CVA/AMPC), cefaclor (CCL), cefotiam (CTM), cefpodoxime (CPDX), cefdinir (CFDN) against 20 strains of bacteria isolated from patients who were subsequently treated with SY5555. MICs of SY5555 for Gram-positive cocci ranged from 0.05 to 0.10 microgram/ml against 10 strains of Staphylococcus aureus. The MIC was < or = 0.025 microgram/ml against one strain of Streptococcus pyogenes, and MICs were from < or = 0.025 to 0.39 microgram/ml against Streptococcus pneumoniae. These MIC values were equivalent or superior to those of the other 5 drugs. MICs of SY5555 for Gram-negative bacilli were 0.39 and 6.25 micrograms/ml against Haemophilus influenzae, and these values were equivalent to those of the other drugs, except CPDX. The MIC of SY5555 was 0.39 microgram/ml against 2 strains of Escherichia coli, and this value was equivalent or superior to those of CVA/AMPC and CCL, similar or inferior to those of CPDX and CFDN, and inferior to that of CTM. The MICs of several drugs were determined for 10 strains of Bordetella pertussis and 30 strains of Campylobacter jejuni isolated from patients before this clinical study. The MICs of SY5555 against the 10 strains of B. pertussis were compared with those of 7 drugs, CCL, CTM, CPDX, ampicillin (ABPC), piperacillin (PIPC), imipenem (IPM) and erythromycin (EM). The MIC of SY5555 was 0.78 microgram/ml against all of the strains. This value was superior to those of CCL, CTM and CPDX, similar or inferior to that of IPM and inferior to those of PIPC and EM. The MICs of SY5555 against the 30 strains of C. jejuni were compared with those of 7 drugs. CCL, CTM, CPDX, CFDN, ABPC, IPM and EM, and the MIC of SY5555 was < or = 0.025 microgram/ml or 0.05 microgram/ml and these values were equivalent or superior to those of the 7 reference drugs. 2. SY5555 dry syrup was administered orally at 30 min. after meals, to a total of 5 patients, at doses of 5.0 and 10.0 mg/kg to 2 patients each and at a dose of 15.0 mg/kg to one patient and the plasma concentrations were determined. Peak concentrations were detected 1 to 3 hours after administration in all patients and the peak concentrations were 0.93 and 1.21 micrograms/ml at the 5.0 mg/kg dose, 2.85 and 5.49 micrograms/ml at the 10.0 mg/kg dose and 5.79 micrograms/ml at the 15.0 mg/kg dose.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗

PubMed1995

Capillaries with fenestrae in the rat soleus muscle after experimental limb immobilization.

Capillaries in the rat soleus muscle were examined by electron microscopy 4 weeks after limb immobilization and compared to those in untreated muscle. Immobilized muscles showed degenerative changes such as dissolution of sarcomeres, vacuoles, and a small increase in connective tissues, including collagen fibers, around muscle fibers. Eight percent of the capillaries in these muscles were found to have fenestrae. The non-nuclear portions of the endothelial cells were extremely thin and were perforated by several fenestrae which were bridged by a single-layered diaphragm. The untreated muscles contained only continuous capillaries. These findings suggest that the occurrence of capillaries with fenestrae in the immobilized muscle may be a result of structural changes in the muscle.

Animals↗

PubMed1994

Scanning electron microscopic observations of the vascular structure of vertebral end-plates in rabbits.

We used scanning electron microscopy to examine the microcirculation in the vertebral end-plates of rabbits. The arteriola arborizes and swells at the end-plate and then coils to make a microvessel loop. This loop is the structure we refer to as a vascular bud. We suggest that these loop structures of the capillaries play a major role in the nutrition of the intervertebral discs.

Animals↗

PubMed1994

[Pharmacokinetic, bacteriological and clinical studies on cefozopran in the pediatric field].

Cefozopran (CZOP, SCE-2787), a newly developed parenteral cephem antibiotic, was administered to children with bacterial infections. We determined its antibacterial activity, pharmacokinetics, efficacy and safety in these patients. 1. Antibacterial activity MICs of cefmetazole, ceftazidime, cefuzonam, flomoxef and CZOP were determined against a total of 19 strains. For Gram-positive cocci, MICs of CZOP ranged from 0.39 to 0.78 microgram/ml against Staphylococcus aureus (3 strains), from 0.05 to 6.25 micrograms/ml against Streptococcus pneumoniae (5 strains), and 12.5 micrograms/ml against Enterococcus faecalis (1 strain). These MICs were generally similar to those of other cephems, but the MIC of CZOP against E. faecalis was lower than those of the other cephems examined. For Gram-negative bacilli, MICs of CZOP were 25 micrograms/ml against Citrobacter freundii (1 strain), and 6.25 micrograms/ml against Pseudomonas aeruginosa (1 strain). These values were similar to or lower than those of other cephems, MICs of CZOP against Haemophilus influenzae (7 strains) ranged from 0.1 to 0.39 microgram/ml. However, the MIC of CZOP against Serratia marcescens (1 strain) was higher than 100 micrograms/ml, and CZOP was as ineffective as the other cephems against this organism. 2. Pharmacokinetics CZOP was administered to children at 20 or 40 mg/kg via intravenous injection, and determinations were made for its serum concentrations, urinary concentrations and concentrations in cerebrospinal fluid (CSF) using the bioassay. Serum concentrations at 30 minutes after administration were 60.4 micrograms/ml with a dose of 20 mg/kg to one patient and 93.9 and 99.0 micrograms/ml with 40 mg/kg to two patients. The corresponding half-lives were 1.55 hours for 20 mg/kg administration, and 1.10 and 3.41 hours for 40 mg/kg, while the AUCs were 136.5 micrograms.hr/ml for 20 mg/kg, and 194.4 and 264.5 micrograms.hr/ml for 40 mg/kg. The rates of urinary recovery in the first 8 hours after administration were 45.0% in the patient receiving 20 mg/kg, and 84.6 and 97.6% in the two patients receiving 40 mg/kg. The concentrations in the CSF determined in 3 patients with purulent meningitis ranged from 2.6 to 16.0 micrograms/ml 1 hour after administration, and the CSF/serum concentration ratio ranged from 6.5 to 39.0%. These values for pharmacokinetic parameters obtained in the bioassay were similar to those obtained using HPLC. 3. Clinical evaluation Forty-eight patients were clinically evaluated. Of these patients, 75% were less than 3 years of age and there were slightly more male children than female children.(ABSTRACT TRUNCATED AT 400 WORDS)

Bacteria↗

PubMed1994

[Bacteriological, pharmacokinetic and clinical studies on biapenem (L-627) in the pediatric field].

Antibacterial activities were determined and pharmacokinetics and a clinical studies were performed on biapenem (L-627), a novel parenteral carbapenem antibiotic, in infections in children. The following results were obtained: 1. MICs of L-627 against clinical isolates were as follows: Among Gram-positive bacteria, MICs were 0.78 microgram/ml to > 100 micrograms/ml against 3 strains of methicillin-resistant Staphylococcus aureus (MRSA), and 0.10 microgram/ml to 0.39 microgram/ml against 8 strains of methicillin-sensitive S. aureus (MSSA), MICs against 5 of them were similar to those of imipenem (IPM), and MICs against 3 of them were slightly higher than those of IPM. MICs were < or = 0.025 microgram/ml to 0.39 microgram/ml against 7 strains of Streptococcus pneumoniae, and were similar to those of IPM, and lower than those of ceftazidime (CAZ) and piperacillin (PIPC). Among Gram-negative bacteria, MICs were 0.78 microgram/ml and 3.13 micrograms/ml against 2 strains of Haemophilus influenzae, and were similar to those of IPM. 2. Maximum plasma concentrations determined by the bioassay method after intravenous infusion of L-627 over 30 minutes at doses of 6.0 and 12.0 mg/kg, respectively, in 2 different pairs of 2 children each (total 4 cases) were observed upon completion of the treatment. Maximum concentrations at a dose of 6.0 mg/kg were 28.8 micrograms/ml and 24.6 micrograms/ml, and at a dose of 12.0 mg/kg were 65.4 micrograms/ml and 39.6 micrograms/ml, exhibiting a dose response. Plasma half lives in the beta phase were 0.97 and 1.20 hours at 6.0 mg/kg, and 0.72 and 0.94 hour at 12.0 mg/kg. Plasma concentrations determined by the HPLC method were lower than those determined by the bioassay. 3. Urinary excretion rates in the first 5.5 hours after the 6.0 mg/kg dose were 81.4 and 75.3%, and after the 12.0 mg/kg dose were 91.0 and 73.8%, and these values were higher than those obtained using HPLC. 4. Concentrations of L-627 in cerebrospinal fluid were determined in 2 cases of purulent meningitis. In one case, 30.3 mg/kg of L-627 was infused intravenously over 30 minutes and concentrations on days 1, 3, 7 and 14 observed at 60, 60, 45 and 45 minutes after respective dosages were 7.60, 1.30, 1.42 and 0.38 microgram/ml. Cerebrospinal fluid-plasma concentration ratio was determined on days 7 and 14 to be 5.5 and 1.2% respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Bacterial Infections↗

PubMed1994

[Concomitant graft replacement of the total aortic root and the transverse aortic arch for type A aortic dissection associated with Marfan syndrome: report of a case].

A 25-year-old man of Marfan syndrome with chronic stage aortic dissection of Stanford type A underwent concomitant graft replacement of the total aortic root and transverse aortic arch. The surgical procedure were performed with an aid of extracorporeal circulation, blood cardioplegia, using the techniques of "open distal anastomosis" under the deep hypothermic circulatory arrest and continuous retrograde cerebral perfusion for cerebral protection during circulatory arrest. The operative techniques consisted of total aortic root replacement using a composite graft with Piehler's and Carrel patch technique for left and right coronary artery, and total arch replacement using en bloc distal arch reconstruction and a composite graft replacement for innominate artery. There were no neurological complications. In the case of Marfan syndrome, type A aortic dissection involving aortic arch should be treated by concomitant graft replacement of the total aortic root and the transverse aortic arch in order to reduce the late risk of aortic dissection or annular dilatation.

Adult↗

PubMed1994

[Basic and clinical studies on cefditoren pivoxil in pediatric field].

Cefditoren pivoxil (CDTR-PI, ME1207) granules, a new oral cephem, was given to pediatric patients with infectious diseases to evaluate antibacterial activities against clinical isolates, pharmacokinetics, clinical efficacy and safety, and the following results were obtained. 1. In sensitivity test, 30 strains were used comprised of 5 species, isolated from the patients before administered with CDTR-PI. Against Staphylococcus aureus, MICs of 7 agents, cefditoren (CDTR), cefaclor, cefixime, cefteram, cefotiam, cefpodoxime and methicillin, were determined. Against other 4 species, MICs of the above 6 agents excluding methicillin were determined. Among Gram-positive cocci tested, the MICs of CDTR were 0.78 to 100 micrograms/ml or higher against S. aureus (16 strains), < or = 0.025 microgram/ml against Streptococcus pyogenes (5 strains), and 0.10 or 0.39 microgram/ml against Streptococcus pneumoniae (2 strains). These values were equal to or lower than those of conventional cephems and of methicillin. Among Gram-negative rods tested, the MICs of CDTR were < or = 0.025 microgram/ml against Haemophilus influenzae (3 strains), and 0.10 or 0.20 microgram/ml against Escherichia coli (4 strains). Also, these values were equal to or lower than those of conventional cephems. 2. When CDTR-PI granules was orally administered in a single dose of 3.0 mg/kg to 1 patient and that of 6.0 mg/kg to 2 patients 30 minutes after meal, plasma CDTR concentrations reached their maxima 4 hours after administration in the former patient and 1 or 2 hours after administration in the latter 2 patients, and the peak plasma concentrations were 1.91, 3.46 and 4.82 micrograms/ml with half-lives of 1.01, 0.81 and 0.88 hours and AUCs of 8.62, 9.89 and 13.52 micrograms.hr/ml, respectively. Dose-dependency was observed for the peak plasma concentrations and AUCs also tended to depend on dose excepting for the AUC in one 6.0 mg/kg patient. 3. The urinary concentrations in the above patients reached their peaks at 4 to 6 hours after administration in one 3.0 mg/kg patient and at 4 to 6 hours and 2 to 4 hours after administration in two 6.0 mg/kg patients, and the corresponding values were 126.0, 195.0 and 234.0 micrograms/ml, respectively. Recovery rates in the first 8 hours after administration were 18.2, 24.6 and 21.3%, respectively. 4. Of 53 patients with 13 diseases, CDTR-PI was clinically judged "excellent" in 32 (60.4%) and "good" in 21 (39.6%), showing excellent efficacy. 5. Bacteriologically, excellent results were obtained, i.e., 29 (96.7%) of 30 strains from 5 species were eradicated. 6. Side effects were observed in none of the 54 patients treated.(ABSTRACT TRUNCATED AT 400 WORDS)

Bacteria↗

PubMed1993

The function of the hypothalamo-pituitary axis in brain dead patients.

In order to find out the function of the hypothalamo-pituitary axis in brain dead patients, pituitary and hypothalamic hormone concentrations were measured and several anterior pituitary releasing tests were carried out in 39 brain dead patients. In addition, cerebral blood flow measurements were simultaneously performed. In almost all cases, the blood concentration of pituitary and hypothalamic hormones were above the sensitivity of the assay. Anterior pituitary releasing tests indicated that efficient functions of the hypothalamus were severely suppressed, while the normal secretory mechanism of the anterior pituitary was partially preserved in brain dead patients. Histological changes of hypothalamic neurons varied from barely detectable ghost cells to nearly normal cells even in the same case. Although, the remaining circulation seemed not to be sufficient enough to maintain integrated hypothalamo-pituitary function, as shown by the examinations of cerebral blood flow, the presence of hypothalamic hormones in the systemic circulation suggests that these hormones were released and carried from the hypothalamus by minimal flow which is preserved even after the diagnosis of brain death.

Adolescent↗